Aerators for mixing water and air are desired to produce a bubbly coherent stream. In addition, aerators have been made which restrict the water flow from a high pressure water supply. A disc with a restricting orifice is placed upstream from the screen. However, these aerators do not take into account the undesireable restriction of the stream at lower water pressure. In other words, these aerators overly restrict the flow from a low pressure water supply.
It is common to have an aerator housing containing a disc with small apertures therethrough. The apertures direct water to flow onto a mixing body. The aerator housing also incorporates an air passage which allows air to enter the aerator and mix with the water that lands on the mixing body. Screens are often mounted below the mixing body and the stream of water passes therethrough.
Attempts have been made to have the screened aerator respond to the pressure of the water supply. An O-ring seated over an opening upstream of the screen can be compressed to increase the restriction at high pressures. However, the screen in these aerators traps water thereon when the faucet is turned off. Evaporation of the water leaves mineral deposits on the screen which over a period of time eventually clogs the screen and deteriorates the water flow therethrough. Secondly, cleaning the screen requires disassembly of the aerator. Thirdly, if the faucet is attached to a low pressure water supply, the screen may undesireably restrict water flow therethrough.
An aerator which responds to pressure in the water supply and yet is able to maximize the water flow therethrough at low water pressure is desireable. It is also desireable to have an aerator that reduces the necessity of cleaning and, when cleaning is necessary, can be cleaned with a minimum amount of effort. It is also desireable to have an audible indication when the aerator is being cleaned.